Tricyanovinyl dyes and their preparation



trite 3,058,977 TRICYANOVHWYL DYES AND THEIR PREPARATION Blaine Chase McKusick and John Richard Roland, Wilmington, DeL, assignors to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware v No Drawing. Filed May 1, 1958, Ser. No. 732,130

' 4 Claims. (Cl. 260-240) This invention is concerned with a new class of tri cyanovinyl dyes and a process for their preparation.

In US. Patents 2,762,810 and 2,762,833 processes are described for preparing C-tricyanovinyl compounds, particularly C-tricyanovinyl aromatic amines and C-tricyanovinyl phenols. These C-tricyanovinyl compounds are highly colored and are useful for dyeing such materials as polyacrylonitrile and polyethylene terephthalate fibers when applied from neutral or acidic media. Heretofore, tricyanovinyl dyes which are stable for application from ized by improved stability for application under alkaline conditions. Other objects will appear hereafter. I

These and other objects are obtainedby providing tricyanovinylarylazomethine dyes wherein a tricyanovinyl group is attached to a carbocyclic aromatic ring or a heterocyclic ring of aromatic character. These new dyes fall into two classes: (1) those in which the tricyanovinyl group is on the nitrogen side of the azomethine (C=N) group, and (2) those in which the tricyanovinyl group is on the carbon side of the azomethine group. The arylene bridge between the tricyanovinyl group and the azomethine group has its bonds stemming from carbon atoms so arranged that if the carbon atom carrying the bond toward the azomethine group is counted as position 1, the tricyanovinyl group is bonded at position 4. In further characterization of the arylene group, it may be said that the corresponding aromatic compound which would be obtained by placing hydrogens at the respective bonds of the arylene group is a compound with a resonance energy of not less than 20 k caL/mole.

Resonance energies of organic compounds and the determination of resonance energies are shown by Linus Pauling in The Nature of the Chemical Bond, second edition, Cornell University Press, 1945, pages 132-139.

The new compounds of this invention are referred to generically as tricyanovinylarylazomethine dyes and fall into two classes. These new classes canbe represented by the following formulas:

a cardinal number no greater than 1, i.e., zero or one; R and R are the same or ditierent and represent a member of the group consisting of hydrogen and hydrocarbyl radicals. (i.e., alkyl, cycloalkyl, aralkyl or aryl hydrocarbon); R is of the group consisting of hydrogen, alkyl, cycloalkyl, aralkyl and aryl; R is 1,4-arylene; R is a memberof the group consisting of 2,5-furylene and 2,5- v pyrrylene; R is vinylene; and R is a. member of the r COOHf-COOY, NO CN and halogens such as --F, --Cl and Br where Y is hydrocarbyl, i.e., aikyl, cycloalkyl, aryl or aralkyl hydrocarbon. A particularly preferred group of dyes, because of their alkali stability, are those where n is l and R is hydrogen.

The process of this invention by which the above co pounds are formed can be illustrated by the following equations:

where n, m and the Rs are as defined in Formulas 1 and 2above. I

The reaction of this invention can be carried out by bringing together tetracyanoethylene and an arylazomethine as shown in Equations 3 and 4 above, preferably into intimate contact for an extended period of time, say of the order of about 1 minute up to 24 hours or more depending on the temperature employed. It is convenient to employ a liquid diluent which is chemically inert to the reactants and products since this facilitates carrying out the reaction.

The reaction can be carried out over a wide range of temperatures, i.e., from 0 C. to C. and above. When it is desired to complete the reaction in a minimum time, it is convenient to heat the reaction mixture. Preferred reaction temperatures are in the range of 2560 C. Pressure is not a critical factor in this process, and atmospheric pressure is accordingly preferred.

As liquid diluents for the practice of this invention there can be used N,N-dimethylformamide, N,N-diethylformamide, N-methylformanilide, N-methylformamide, formamide, N-methyl-N-ethylacetamide, N,N-dimethylacetamide, N,N-diethylacetamide, tetramethylurea, tetraethylurea, pyridine, dimethylsulfoxide and mixtures of these liquids. The dialkyl lower alkanoamides are the preferred class of solvents.

For practical yields of dyes, it is preferred to employ approximately equimolar quantities of tetracyanoethylene and the arylazomethine. However, the reaction will take place when the reactants are employed in any proporti on, and molar ratios within the range of 1:2 to 2:1

are preferred.

In the following examples parts are by weight unless otherwise indicated. Example II represents a preferred embodiment of the invention.

EXAMPLE I About five parts each of. benzaldehyde phenylhydrazone and tetracyanoethylene are mixed with about 50 parts of pyridine. The mixture turns greenish yellow for a short time, due to the formation of the pi complex of tetracyanoethylene with pyridine. After warming the mixture at 60-l00 0., this color quickly gives way to the 60 C. For a brief period the heat of reaction cairies the temperature to 90 C. It is maintained at 50-60 C.

.for the remainder of a total reaction time of ten minutes.

The reaction mixture is cooled to C. and filtered to recover dark green crystals of 2-p-dimethylaminophenyl-l-p-(u'icyanovinyl)anilinoazomethine which show a golden iridescence when dried. An acetone solution of this compound is darkblue and shows absorption maxima at 580 millimicrons, molecular extinction coeffideep magenta color of Z-phenyl-l-p-j(tricyanovinyl)-anilinoazomethine which starts to form within a few seconds and is complete withina-few minutes. Dilution of the red solution of the dye.

EXAMPLE II The dye of Example I is prepared by mixing 38 parts of tetracyanoethylene and 59 parts of benzaldehyde phenylhydra'zone in 94'parts of dimethylformamide. The mixture warmed to 60 C. The exothermic reaction the temperature briefly to 80 C.- The reaction mixture is cooled to 60 C. and held at that temperature for a total reaction time of ten minutes. The mixture is then cooled to 0 C., and reddish black crystals of 2- phenyl-l-p-(tricyanovinyl)anilinoazomethine are collected by filtration and recrystallized from glacial acetic acid. An al.Calcd. for (I fi -N C, 72.8; H, 3.70; N, 23.60. Found: C, 72.7; 'H, 3.99; N, 23.13. A spectrophotometric analysis of an acetone solution of dye shows it to have anU-absorption maximum .at 520 millimicrons with a molecular extinction coeficient of 46,300. The infrared absorption spectrum shows a NH band at 3.05 microns, a band for unsaturated CH at3.25 microns, a band for conjugated cyano at 4.5 microns, and bands for unsaturated carbon carbon and carbon-nitrogen at'6.2, 6.5 and 6.75 millimicrons.

EXAMPLE III About five parts each of acetophenone phenylhydrazone andttetracyanoethylene in about 100 parts of dimethylformamide are warmed at 60--90" C. for several minutes. 2 -methyl-Z-phenyl-l-p-(tricyanovinyl) anilinoazomethine forms as a deep red dye.

EXAMPLE IV About five parts each of benzophenone anil and tetracyanoethylene in about 100 parts of dimethylformarnide are warmed at 60-90 C. for several'minutes. 2,2- diphenyl-l-p-(tricyanovinyl)phenylazomethine forms a deep orange-red dye.

EXAMPLEV p-Dimethylaminobenzaldehyde 'phenylhydrazone (59 parts) and 32 parts of tetracyanoethylene are mixed with about 94 parts of dimethylformamideand heated at 50- 7. reaction mixture with an excess of ethanol gives a blood Found: C, 70.25; H, 4.75; N, 24.6.

cient 29,600, and at 360 millimicrons, molecular extinction coefiicient 14,900.

AnaL-Calcd. for 0,,H,,N,= c. 70.6; 4.72; N, 24.4.

r EXAMPLE VI About five parts each of p-nitrobenzaledehyde phenylhydrazone and tetracyanoethylene are warmed in about 100 parts of dimethylformamide for ten minutes. 2-pnitro phenyl 1 p (tricyanovinyl)anilinoazomethine is formed asv a brilliant red dye.

EXAMPLE VII EXAMPLE VIII About five parts each of cinnamaldehyde phenylhydrazone and tetracyanoethylene in about 100 parts of dimethylformamideare warmed at -90 C. for five minutes. At the end of this time, reaction is complete and the solution is deep magenta in color. The dye formed 1s 2-styryl-1-p (tricyanoviny1)anilinoazomethine. The absorption maximum of this dye is at a wave length between those for the dyes shown in Examples I and V.

EXAMPLE IX About five parts each of phenyl(p-dimethylaminophenylmethylene) amine and tetracyanoethylene are warmed in about parts of dimethylformamide. 2-pdimethylamino 2 phenyl-l-p-(tricyanovinyDphenylazomethine is formed as a deep orange-red dye.

EXAMPLE X Piperonal phenylhydrazone parts) and 64 parts of tetracyanoethylene are heated at 45-50 C. in 94 parts of dimethylformamide 2- (3,4'-methylenedioxyphenyl) 1 p (tricyanovinyl)anilinoazomethine is formed as dark purple crystals having a metallic luster when dry. The yield is 107 parts (62%), and the dye melts at 265 C. An acetone solution of the dye shows an absorption maximum at 540 millimicrons with a molecular extinction coeflicient of 45,300.

Anal.Calcd. for C H O N N, 20.52. Found: N, 20.05.

EXAMPLE XI About five parts each of l-naphthaldehyde phenylhy- CI, 10.7; N, 21.15,

Veratraldehyde phenylhydrazone (223 parts) is dissolved in 472 parts of dimethylformamide and heated to 49 C. Finely powdered tetracyanoethylene (111 parts) is added portionwise with agitation while the reaction mixture is maintained at temperatures in the range of 40-50 C. When the reaction is complete, the mixture is cooled to C. and filtered torecover glistening green crystals of 2-(3,4-dimethoxyphenyl)-1-p-(tricyanovinyl)- anilinoazomethine. The yield is 180 parts (58%). A portion of the dye recrystallized from butyl alsohol melts at 275 C. An additional 131 parts of 2-(3,4-dimethoxyphenyl) 1 p-(tricyanovinyl)anilinoazomethine, melting at 271 C., is obtained by precipitation of the original filtrate in ice. An acetone solution of this dye shows an absorption maximum at 542 millimierons with a molecular extinction coefficient of 44,600.

Anal.--Calcd. for C H O N C, 67.25; H, 4.21; N, 19.6. Found: C, 67.15; H, 4.61; N, 20.33.-

EXAMPLE Xnt About five parts each of cuminicaldehyde phenylhydrazone and tetracyanoethylene are warmed in about 100 parts of dimethylformamide. 2-p-isopropylphenyl-1-p- (tricyanovinyl) -anilinoa zometh ine forms as a brilliant redmagenta dye.

EXAMPLE XIV p-Diethylaminobenzaldehyde phenylhydrazone (190 parts) and 567 parts of dimethylformamide are warmed at 50-55 C. and 910 parts of tetracyanoethylene is added portionwise. 2 p diethylaminophenyl 1 p (tricyanovinyl)-anilinoazomethine separates in the form of dark green crystals which are recrystallized from normal butyl alcohol. The dye has a metallic luster when dry and melts at 267 C. An acetone solution of the dye shows absorption maxima at 592 millimierons (molecular extinction coefficient, 41,200), 419 millimierons (molecular extinction coeificient, 7,160), and 3 68 millimierons (molecular extinction coefiicient, 22,100).

Anal.Calcd. for C H N C, 71.75; H, 5.43; N, 22.82. Found: C, 72.06; H, 5.79; N, 22.10.

EXAMPLE XV To 16.2 parts of N-butyraldehyde phenylhydrazone in 20 parts of dimethylformamide is added 12.8 parts of tetracyanoethylene. The tetracyanoethylene isadded portionwise over a period of about minutes. The reaction I mixture is cooled and agitated to maintain the temperature at 4550 C. The dye is precipitated by pouring the reaction mixture onto well-stirred, finely-ground ice. 2- propyl-l-p-(tricyanovinyl)anilinoazomethine is obtained as a bright red dye.

EXAMPLE XVI Furfural phenylhydrazone (18.6 parts) and 12.8 parts of tetracyanoethylene are condensed in dimethylformamide solution at 28-33 C. The mixture is then poured into crushed ice. 1-ani1ino-2-(5-tricyanovinyl-2-furyl)- azomethine which separates is filtered off and recrystallized from butyl alcohol. This yields 14.2 parts of greencrystals melting at 249 C. The yield is 49.5% of the theoretical. An acetone solution of this dye has an absorption maximum at 588 millimierons and a molecular extinction coeflicient of 32,400.

' parts.) .This dye melts at 280 C. and an acetone solution has absorption maxima at 360 and 590 millimicrons with molecular extinction coeflicients of 23,300 and 7 increases to 40 C.

0 Anal.-Calcd. for C H ON C, 66.9; H, 3.14; 24.39. Found: C, 67.49; H, 3.52; N, 24.51.

EXAMPLE XVII Formaldehyde phenylhydrazone (1.5 parts) and 1.6

parts of tetracyanoethylene are condensed in 20 parts of dimethylformamide while stirring and warming the mixl-p-(tricyanovinyl) anilinoazomethine ture at 40-45 C. is formed as a bright red dye.

EXAMPLE XVIII p-Dimethylaminobenzaldehyde methylphenylhydrazone 32,200, respectively.

- Anal.-Calcd. for C21H13N5I C, 71.2; H, 5.08; N, 23.7.

Found: C, 70.80; H, 5.18; N, 25.81.

EXAMPLE XIX m-Thenaldehyde phenylhydrazone (10.1 parts) and 6.4 parts of tetracyanoethylene are condensed by stirring and heating at 45-55" C. in 10 parts of dimethylformamide. The reaction mixture is cooled at 0 C. overnight and filtered. The solid 2-(2-thienyl) 1 p (tricyano'vinylltanilinoa-zornethine obtained is recrystallized from acetic acid. Thisyields 0.4 part of magenta crystals. The filtrate from the dye is poured into a mixture of ice and water. The solid 2-(2 thienyl) 1 p (tricyanovinyl)- anilinoazomethine obtained is filtered and recrystallized from butyl alcohol. This yields 102 parts of dye melting at 270. C. An acetone solution'of the dye has an absorption maximum at 535 millimierons, molecular extinction coeificient of 41,500.

Anal.-Calcd. for C H SN C, 63.48; H, 2.97; N, 23.1. Found: C, 64.00; H, 3.27; N, 23.26.

EXAMPLE XX To a solution of 19.5 parts of trifluoroacetaldehyde I ,1 phenylhydrazone in dimethylformamide there is added 11.3 parts of tetracyanoethylene in small portions. At Ii the start the reaction is exothermic and the temperature l-ptricyanovinyl) aniIino-Z-trifiuoromethylazomethine separates as a bright orange-yellow dye.

EXAMPLE XXI and 560 millimierons with molecular extinction coefii cients of 21,000 and 38,600 respectively.

EXAMPLE XXII Pyridine-3-carboxaldehyde phenylhydrazone (8.6 parts) I 7 is dissolved in 25 parts of dimethylformamide. This solution is stirred at 40 -45 C. while adding 6.4 parts of tetracyanocthylene. The reaction mixture is cooled and filtered. The precipitate is recrystallized from acetic acid; this yields 1.9 parts of 2-(3-pyridyl)el-p-(tricyanovinyD- anilinoazomethine melting at 231-233 C. The filtrate is precipitated by pouring into stirred ice and water. This yields an additional fraction which is recrystallized from butyl alcohol. This yields an additional 1.8 parts of dye. This dye has an absorption maximum at 512 millimicrons, extinction coeflicient 27,400. V

Analysin -Called; for C qH N C, 6 8.5; H, 3.36; N, 28.2.- Found: C, 68.60; H, 3.50; N, 27.60.

EXAMPLE XXIII To a'solut ion of 55 parts of acetophenone phenylhydrazone in142 parts of dimethylformamide at 4050 C. '1 33.5 parts of tetracyanoethylene is added in small portions over a period of 20 minutes. Heating is continued for another 10 minutes. The mixture is cooled overnight and triturated with acetic acid. 2-methyl--2.-phenyll-p-(tricyanovinyl)anilinoazomethine separates as a deep red dye and is collected by filtration. One portion is recrystallized. from acetic acid and another portion from EXAMPLE XXIV 'A solution of 74 par-ts of acetone phenylhydrazone in 95 parts of dimethylformam'ide is prepared and warmed '10- 3510. To this there are added 64 partsof tetracyanoethylene in small portions over a period of 20 minutes. The reaction is mildly exothermic, and the mixture is intermittentlyicooled to maintain the temperature at 30-40 C. 2,2-dimethyl-l-p-(tricyanovinyl)anilinoazomethine is formed as a brightorange-red dye. The reaction mixture is stirred into a mixture of 1000 parts of finely chopped iceand a little water. This crude dye has absorption maxima at 511 and 380 millimicrons,-ex-

tinctioncoetficients -of'2860, 3190, and melts at 100- EXAMPLE XXV Part A'.Prepa mtion of I-Formyl-Z-(p-Tricyano- "vinylphenyDHydrazine A solution of 13.6 parts of l-formyl-Z-phenylhydrazine in 24 parts of dimethyformamide is prepared. This solution is stirred at 2530 C. while 12.8 parts of tetracyanoethylene is added over a period of 15 minutes. The mix- 'ture is allowed to stir an additional 15 minutes at 25- 30 C; The reaction mixture is then poured onto 300 parts of ice containing about 10 parts of glacial formic acid. After the ice has melted, the aqueous top layer is decanted. The remaining viscous mass is trituratedwith glacial formic acid until solidification occurs. The solid is filtered out and recrystallized from ethyl alcohol. This yields 4.3 parts of l-formyl-Z-(p-tricyanovinylphenyD- hydrazine, melting with decomposition on a block at 215- 216 C. An acetone solution of this productshows an absorptionvrnaximum at 460 millimicrons with a molecular extinction co'eflicient of 27,400.

' AnaL-Calcd. for C H NO: N, 29.55. Found: N, 29.51.

8 Part B A mixture of 23 parts of l-formyl-Z-(tricyanovinylphenyl)hydrazine and 15 parts of benzaldehyde is heated 5 to reflux for 25 minutes in 1580 parts of alcohol plus 500 parts of water plus 25'parts of concentrated aqueous hydrochloric acid. After about 12 minutes the red-brown color due to the formly hydrazide changes to a bright magenta. The reaction mixture is cooled slightly and poured onto'a well-stirred mixture of 10,000 parts of ice. After the ice melts, the solid dye is collected on a filter and recrystallized from n-butyl alcohol. This yields 20 parts of 2-phenyl-l-p-(tricyanovinyl)anilinoazomethine which is identical with the product of Example 11. The identity of the two dyes is established by identity of their infrared andvisible absorption spectra.

EXAMPLE XXVI A mixture of 23 parts of l-formyl-Z-(p-tricyanovinylphenyl)hydrazine and 15 parts of p-dimethylaminobenzaldehyde is refluxed in 1580 parts of alcohol, 500 parts of water, and 25 parts of concentrated aqueous hydrochloric acid for minutes. The dye is isolated and recrystallized as in Example XXV, Part B. This yields 28 parts of 2p-dimethylaminophenyl-1-p(tricyanovinyl)anilinoazomethine, a blue dye which is shown by infrared and visible spectroscopy to be. identical with the dye described in Example V. V

. EXAMPLE XXVII A mixture of 23 parts of l-formyl-Z-(p-tricyauovinylphenyl)hydrazine and 15 parts of furfural is refluxed in aqueous alcohol containing hydroc'hloricacid as in Example XXVI. The dye is isolated and recrystallized as described in Example )QiV, Part B. This yields 26 parts of 2-(2-fury1),-1-p-(tricyanovinyl)anilinoazomethine havingan'absorption maximum at 530 millimicrons and a molecular extinction cocfiicient of 43,000.

' Analysis.-Calcd. for C I-I N O; C,66.9; H, 3.14; N, 24.39. Found: C, 67.08; H, 3.36; N, 22.54.

The infrared absorption spectrum of this dye differs from that of the dye of Example XVI. These have significantdifierences throughout the spectrum. In particular, the product of Example XXVII has strong infrared absorption bands at 832 and 750 cm." showing parasubstituted phenyl, confirmed by weaker bands at 1015, 1072, 1102, 1182 cmr In contrast, the product of Example XVI has strong infrared absorption bands at 753 and 691 cm. characteristic of monosubstituted phenyl and confirmed by weaker bands at 1028, 1068,

and 1163 emf- I g EXAMPLE XXvnI A mixture of 23 parts of 1-formyl'-2 -(p-tricyanovinylphenyDhydrazine and 13 parts of .fl-(Z-furyDacrolein is condenser by refluxing in aqueous alcohol containing hydrochloric acid andworked up as in Example XXV, Part u B. This yields '21 parts of 2-fi-(2-furyl)vinyl-1-p-(tricyanovinyl) anilinoazomethine, a purple dye which in acetone solution shows an absorption maximum at 545 millimicrons and a molecular extinction coeflicient of 50,100.

EXAMPLE XXIX A mixture of 23 parts of l-formyl-Z-(p-tricyanovinylphenyDhydrazine and 15 parts of indole-S-carboxaldehyde is condensed and worked up as in Example XXV,

Part B. This yields 33 parts of 2-(3-indolyl)-1-p-tricyanovinyl)anilinoazomethine. An acetone solution of this dye has an absorption maximum at 573 millimicrons and a molecular extinction coeflicient of 43,300.

AnaL-Calcd. for C H N C, 71.4; H, 3.57; N, 25.0.

; Found: C, 71.4; H, 3.88; N, 24.51.

9 EXAMPLE XXX Reaction of 50 parts of indole-3 -carboxyaldehyde phenylhydrazone and 27 parts of tetracyanoethylene in 95 parts of dimethylformamide at 40-45 C. for 20 minutes yields 20 partsof 2-(3-indolyl)-1-p-(tricyanovinyl) anilineazomethine in the form of a bright blue dye having intuned and visible spectra identical with the spectra of the product of Example XXIX.

' EXAMPLE XXXI A mixture of 23 parts of l-formyl-Z-(p-tricyanovinylphenyl)hydrazine and 12 parts of salicylaldehyde is condensed and worked up as in Example XXV, Part B. This yields 16 parts of Z-o-hydroxyphenyl-l-p-(tricyanovinyl)anilinoazomethine in the form of a purple dye having an absorption maximum at 520 millicrons and a molecular extinction coefficient of 44,400.

EXAMPLE XXXII v A solution of 188 parts of salicyladlehyde phenylhydrazone and 128 parts of tetracyanoethylene in 570 parts dimethylformamide is stirred-and heated at 45-50 C. for about 20 minutes. The reaction mixture is precipitated by pouring onto well-stirred ice. The precipitated dye is recrystallized from n-butyl alcohol. This yields 123 parts of 2-o-hydroxyphenyl- 1-p-(tricyanovinyl)- anilinoazomethine. The infrared and visible spectra are identical With/those of the product of Example XXXI.

Anal.Ca1cd. for C H N O: C, 69.0; H, 3.52; N,

' 22.35 Found: C, 68.69; H, '3.54; 'N, 21.75.

EXAMPLE XXXHI A mixture of 23 parts of 1-formyl-2-(p-tricyanovinylphenyl)hydrazine and parts (excess) of n-butryaldehyde is condensed and worked up as in Example XXV, Part B. This yields 17 parts of 2-propyl-l-p-(tricyanovinyl) anilinoazomethine, a bright red dye having an absorption maximum at 508 millimicrons and a molecular extinction coeflicient of 42,600. The product is identical to the product of Example XV.

. Anal.Ca.lcd. for C H N C, 68.5; H, 4.95; N, 26.6. Found: C, 69.10; H, 5.07; N, 25.67.

EXAMPLE xxx'rv q fl-2-(fury1)acrolein phenylhydrazone (210 parts) is dissolved in 945 parts of dimethylformamide; 128 parts of tetracyanoethylene is added and the mixture is allowed to stand at room temperature for Z-hours. During this time reddish-brown crystals of l-anilino-Z- [B-(S-tn'cyanovinyl- 2-furyl)]vinylazomethine separate. These crystals are separated by filtration, washed in ethyl acetate and dried. The yield is 158 parts. An acetone solution of this dye is blue and shows an absorption maximum at 615 millimicrons. The dye melts at 150 C. when heated rapidly,

but decomposes below 150 C. when heatedslowly.

When the following arylazomethine compounds are treated with tetracyanoethylene in dimethylformamide solution in the manner of Example III, the indicated tricyanovinylarylazomethines are obtained.

TABLE I Arylazomethine Starting Material Tricyanovinylarylazomethine 7 Product Q-anthraldehyde phenylhydrazone.

S-indoleawtaldehyde phenylhyazone. Zpyridinecarboxaldehyde phenylhydrazone. anilinoazomethine. glucose phe ylosazone-.--.-----..- 2-(l-phenylhydrazono-2,3,4,5-tetrahydroxyamyD-l-pdtrrcyanovinyDanthnoazomethme.

2-(Q-anthryl)-1-p-(trioyanovinyl)- anilinoazomethine.

2-(Ii-indolylmethyl)-1-p-(tricyanovinyDanilinoazomethine.

TABLE I-Contlnned A'rylazomethine Starting Material Tricyanovinylarylazomethine Product 7 4-dimethylamino-Lnaphthaldehyde phenylhydrazone.

2,4-dimethoxybenza.ldehyde phenylhydrazone.

2,4-bisd1methylaminobenzaldehyde phenylhydrazone.

p-dodecylbenzaldehyde phenylhydrazone.

Lenilino-2-(1,3,3-trimethyl-2-lndolylidenemethybazomethine.

hexahydrobenzaldehyde phenylhydrazone. cyclopropanecarboxaldehyde phenylhydrazone. p-methylaminobenzaldehyde phenylhydrazone. p-dibenzylaminobenzaldehyde phenylhydrazone. p-(ti-cyanoethylmethylamino)benzaldehyde phenylhydrazone.

p-(B-benzoyloxyethylmethylamin o) benzaldehyde phenylhydrazone. 4-meth0xybenzaldehyde-JS-sulionic acid phenylhydrazone.

phenylhydrazone of ethyl ester of benzaldehydeo-sultonic acid.

terephthalaldeh'ydic acid phenylhydrazone.

phenylhydrazone of methyl ester of terephthalaldehydic acid.

quinoline-Z-carboxaldehyde phenylhydrazone.

isoxazoleJS-carboxaldehyde phen- -ylhydrazone,

eyclohexanons phenylhydrazoneturturaldehyde semicarbazone iurfuraldehyde oxime pyrrole-Z-carboxaldehyde p-chlorophenylhydrazone. pyrrole-Z-carboxaldehydo O-methyloxime. pyrrole-2-carboxaldehyde thiosemicarbazone. hexafluorocyclobutanone phenylhydrazone.

2-(4-dirnethylagnino-l naphthyl)-1- p (tneyanovmyl)amlinoazomethine.

2-(2,4-dimethoxyphenyl)-1-p-(tricyanovinyl) anilmoazomethine.

2(2,4-bisdimethylaminophenyD-lp-(glicyanovinynanilinoazoin me. 2-(p-dodecylpheny1) l p-(tricyanovinyl) anilinoazomethme.

trimethyl-2indolylidenemet yDazomethine. 2-cyclohexyl-l-p-(tncyanovinyD- anilinoazomethine. 2-cyclopropyl-l-p-(trieyanovinyD- anilinoazomethine. 2-p-methylamino henyl-l-p-(tricyanovinyDani inoazomethine. 2-pdibenzylamlnophenyl-l-p-(tricyanovinynanilinoazomethiue. 2-p(fl cyanoethylmethy lamino)- phenyl-l-p-gtrieyanovmynanllinoazo-met ine. 2 p-(fl-benzoyloxyethylmethylamino) phenyl-Lp-(trieyanovinyl) anilinoazomethine. 2-(4-methoxy-3-sulfophenyD-l-p- (trlcyanovinyl)anilinoazomethme. 2-(Z-cthoxysultonylphenyD-l-p (tricyanovinyl)anilinoazomethme. 2-(p-carboxyphenyD-l-p-(tricyanovmyl)anilinoazorneth1ne. 2-p-(methoxycarbonybphenyl-l-p- (tncyanovmyl)amlinoazomethme. 1 2-(iquinolyl)-1-p:(trleyanovinyl)- auilinoazomethine. 2-(3-1soxazolyD-1-p-(tricyanov1nyl) anilinoazornethine. p-(tricyanovinyDphenylhydrazonocyclohexane. 2-(5-tricyanovinyl-.Z-furyl)-lureidoazomethine. l-hydroxy-Z-(5-tricyanovinyl-2- furyl) azomethine. l-p-chloroauilino z-(itricyanovinyl-Z-pyrrolyDazomethiue. l-methoxy-2-(5-tricyanovinyl-2- pyrrolyl) azomethine. l-thioureidov2-(5-tricyanoviny1-2 pyrrolyl) azomethme. p-(trieyanovinyDphenylhydrazonohexafluorocyclobutane.

The compounds of this invention have been named as tricyanovinylary-lazomethines since this expression recites generically the whole structure which is common to all of these compounds. Following the customary precedence of atoms in numbering an organic compound, the nitrogen atom of-the azomethine group is numbered 1 and the car bon atom is numbered 2. However, there are other meth-- g. of 2,4-dinitrophenylhydrazine and 2 ml. of concentrated hydrochloric acid. The reaction mixture is cooled in ice and filtered. This yields a brownish red, needle-shaped solid weighing 0.23 g. After air-drying, it is found to melt sharply at 238 C. I A mixed melting point with authentic benzaldehyde 2,4-dinitrophenylhydrazone is 238-239-C. Recrystallization from alcohol gives no change in color, and the melting point is 238-239 C. From this it is evident that the hydrazine of the dye molecule interchanges I lulose acetate is I with 2,4-dinitrophenylhydrazine according to the follovvmg equation:

ene terephthalate by the following procedure. A paste is made from 1.8 parts of dye and about 1.8 parts of v The p-tricyanovinylhydr'azine portion of the dye is tenta- .tively identified by reaction of the mother liquor from "the above hydrazine interchange with a small amount of p-dimethylaminobenzaldehyde. A drop of this reaction mixture is chromatographed on paper. This separates "the bright blue dye of Example V from the other material. This shows an alternative synthesis of tricyanovinyl dyes according to the equation:

The use of the tricyanovinylarylazomethines t this invention as dyes is illustrated as follows:

DYEING EXAMPLE A.

One-half part of Z-phenyI-I-p-(tricyanovinyl)analino- .azomethinqprepared as shown in Example II, is dissolved in 25 parts of acetone and poured into 200 parts of water 1 containing 5 parts of glacial acetic acid. S ke'ins of polyethylene terephthalate and cellulose acetate yarns are immersed in the resulting dye bath and heated at 100? C. for

l the cellulose acetate yarn is dyed a bright magenta color.

DYEING EXAMIBLE B One-half part of Z-p-dimethylaminophehyl-l-p-(tricya'novinyDanilinoazomethine is dissolved in 50 parts of acetone and poured into 200 parts of water contaimng about-10% accticacid. Skeins of polyethylene terephthalate and cellulose'acetate yarns are immersed in this dye bath and heated at 100 C. for one hour. The polyethylene terephthalate is dyed a pale blue, and the celdyed a dull blue color.

DYEING EXAMPLE 0 1 V v A dye bath is prepared by pouring a solution of 0.0 part of 2-phenyl-1-p-(tricyanovinyl)anilinoazomethine in 10 parts of acetone into a well-stirred solution of 200 parts of water and 50 parts of an aqueous solution of a sulfonated lignin dispersant (Marasperse, Marathon Company) containing 0.001 part of dispersant per part of water. Swatches of cellulose acetate, cotton, polyethylene terephthalate, and nylon fabrics are immersed in the dye bath and heated at 80-909, C. for one hour. The cellulose acetate is dyed a bright magenta color; the cotton is dyed a pale pink; the polyethylene terephthalate is dyed a dark pink; and the nylon is dyed a deep violet color.

DYEING EXAMPLE D A dye bath is prepared as in dyeing C except that the dye employed is Z-p-dimethylaminophenyl-l-p-(tricyanovinyl)anilinoazomethine. This dye bath dyes cellulose acetate and polyethylene terephthalate fabrics a blue color and nylon fabric a deep blue-green color.

DYEING EXAMPLE E The dyes indicated in Table II are applied to polyethyldimethylformamide. The paste is dissolved in suflicient water and acid to give a total dye bath of 180 parts (1% dye) at pH 4.5. Five parts of polyethylene terephthalate fiber is added to the bath and the temperature is raised to 120 C. for one hour by heating in a metal bomb in 15 lbs. pressure. The tabricis removed from the bomb, rinsed and dried, and the color-is observed.

TABLE II Color on 'Poly- I Dye ethylmu pnthat-21L 2-p-dimethylaminophenyl-l-p-(tricyanovinyl)- light blue.

anillnoazomethine. 2-p-(fi-cyanoethylmethylamino)phenyl-l-p-(trllight reddish-blue.

cyanov-ln D-anilinoammethlns. l-auilino-Z-iii-tric anovinyl- -furyl)azomethine strong blue. 2-(2-thienyl -1-ptricyauovinyDanlllnoazored-violet.

me 2-(p-tolyl)-1-p-(trieyanovinyl)anllinoazomethino-..- blue-red.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations are to be understood therefrom. The invention is not limited to the exactdetails shown and describe; for obvious modifications will occur to those in the art.

The embodiments of the invention in which an exclus1ve property or privilege is claimed are defined as follows:

1. Z-phenyl-l-p-(tricyanovinyl)anilinoazomethine.

2. Z-p-dimethylaminophenyl- 1 -p-(tricyanovinyl)-anilinoazomethine.

3. 1-(anilino-2-(S-tricyanovinyl-Z-furyl)-azomethine.

4. Tricyanovinylarylazomethines selected from the group consisting of I and II, wherein I is of the formula 2 wherein R, R and n have the same significance as above; n is a cardinal number selected from the group consistingof zero and one; R is selected from the group conslstzng of unsubstituted 2,5-furylene and unsubstituted 2,5-pyrrylene; R is vinylene and R" is selected from the group consisting of phenyl, p-chlorophenyl, hydroxy, OTHER REFERENCES 2,762,810 Heckert Sept. 11, 1956 alkoxy carbamyl and thiocarbamyl' Bergmann: The Chemistry of Acetylene and Related References Cited in the fil of this Patent Compounds, pp. 79-80, Interscience Publishers Inc., New

UNITED STATES PATENTS 5 York (1 48)- Taylor et al.: Journal of the Amencan Chem1cal Soc.,

2,339,335 Hacked J 2, 1959 PP- 2456-2464 

3. 1-(ANILINO-2-(5-TRICYCNOVINYL-2-FURYL)-AZOMETHINE.
 4. TRICYANOVINYLARYLAZOMETHINES SELECTED FROM THE GROUP CONSISTING OF I AND II, WHEREIN I IS OF THE FORMULA 